Push zstd::chunked compressed container images to another tag

[travier]

Using a better compression algorithm will mean smaller container images in the registry and faster pulls.

As the spec does not support multiple compression algorithms for a single tag, we should push those images to another tag.

See:

• https://www.redhat.com/sysadmin/faster-container-image-pulls
• https://github.com/containers/podman/discussions/15126
• https://github.com/containers/podman/discussions/15113
• --compression-format= for podman: https://docs.podman.io/en/latest/markdown/podman-push.1.html
• --dest-compress option for skopeo: https://github.com/containers/skopeo/blob/main/docs/skopeo-copy.1.md
• https://github.com/containers/storage/pull/775
• https://github.com/containers/image/pull/1084
• https://github.com/moby/moby/issues/28394#issuecomment-1822741770
• https://github.com/opencontainers/image-spec/issues/803#issuecomment-745335277

[travier]

According to https://fedoraproject.org/wiki/Changes/zstd:chunked, container engine mostly support this format now.

But that would require some testing to not break older systems. So the push 2 times route is probably the safest in the short term. It should be reasonably easy to do.

[travier]

Apparently it's possible to push both formats using a manifest list: https://discussion.fedoraproject.org/t/switch-fedora-container-images-to-support-zstd-chunked-format-by-default/123712/8

I will give this a try.